The present invention relates generally to a loading system for loading a magnetic tape cassette in a recording and/or reproducing apparatus. More specifically, the invention relates to an automatic loading system in a recording and/or reproducing apparatus designed for use with magnetic tape cassettes having a front pivotal closure lid for openably closing the front opening of the magnetic tape cassette, and a sliding closure member covering a lower cut-out in the cassette housing. Still more specifically, the invention relates to a magnetic tape cassette recording and/or reproducing apparatus including a front-loading magnetic tape loading system, specifically designed for recording and/or reproducing magnetic tape cassettes of the type which have a front pivotal closure lid for openably closing the front opening of the magnetic tape cassette, and a sliding closure member covering a lower cut-out in the cassette housing, such as a peripheral-scan pulse-code modulated (PCM) audio cassette.
In recent years, various recording and reproducing apparatus have been developed to convert analog signals, such as audio signals and the like, into digital signals, e.g. PCM signals, which are then recorded on and reproduced from magnetic tape serving as a recording medium. Some of these apparatus employ rotary heads in order to achieve a relatively high recording density. Recording and reproducing apparatus specifically designed to record and reproduce PCM signals and employing a rotary head will be referred to as a "PCM recorder" throughout the disclosure. A PCM recorder, at first, pulls a loop of magnetic tape out through a front opening of the cassette and winds the tape around a rotary drum accommodating the rotary head and then recording and reproduction is performed. In such digital recording and reproducing systems, oily deposits, such as fingerprints or the like, and/or dust adhering to the tape surface may cause dropout of reproduced signals.
Various approaches have been tried to protect the magnetic recording medium. For example, a closure lid may be used to retractably cover the front end opening of the cassette, through which the tape is extracted for access by a rotary head. This closure lid is held closed while the tape is not in use and is moved to an open position when the cassette is inserted into the PCM recorder. In this earlier approach, a drawback may be encountered when the closure lid is unintentionally or accidentally opened, exposing the tape to oily fingerprints, dust and so forth while it is not in use. A locking mechanism which can conveniently lock the closure lid in its open and closed positions could resolve this problem.
Such a magnetic tape cassette which has a tape-protective pivotal lid has been disclosed in the U.S. Pat. No. 3,980,255, issued on Sept. 14, 1976, to Akio SERIZAWA and assigned to the common assignee to the present invention. In the disclosure, the magnetic tape cassette for a magnetic recording and/or reproducing apparatus has a housing with an opening through which the tape can be withdrawn from the cassette housing for the recording and reproduction of signals thereon, as by one or more rotary heads, and a lid is provided to normally close the housing opening when the cassette is not in use and thereby protect the tape from damage. The lid is associated with a latch mechanism for locking the lid in its closed position, and this latch mechanism can be released by inserting the cassette into a cassette holder. Recently developed magnetic tape cassettes additionally include sliding closures or shutters which cover a lower opening which allows entry of loading devices and tape reel drives of the recording and reproducing apparatus. These sliding closures can also move between open and closed positions. The sliding shutters are associated with lock mechanisms which lock them in both their open and closed positions.
For loading such magnetic tape cassettes having a pivotal closure lid and a sliding closure member for recording and/or reproduction, it has become necessary to actuate the pivotal lid and the sliding closure member so that they may be moved to the open position when loaded into a recording and/or reproducing apparatus and to the closed position when ejected from the recording and reproducing apparatus.